[CLUE-Tech] Jounaling Filesystems Ext3 or Reiser Which to use?

[Dennis J Perkins]

Mike Benavides wrote:
> What is the pros and cons of each. Reiser stores the filesnames
> themselves in a B tree, to give it a performance throughout the file
> size spectrum. Ext3 is more a black box that it is more advanced Ext2
> system developed by Dr. Tweedy et al...
> 
> Mike
> 
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Ext3 is basically ext2 with journaling added.  This gives you a robust 
workhorse with minimal changes.  The similarity is so great that you can 
switch back and forth between ext2 and ext3.  Apart from the new ext3 
code in the kernel, the major change is the addition of a journaling 
file. It does have one feature that is apparently lacking in the others; 
it can journal data as well as metadata (metadata is the information 
about the file.)  Performance is reported to be good and it can 
outperform Reiser at times.  One disadvantage is that if the journal ing 
file gets corrupted, you can have problems.  On the plus side, if you 
can boot from floppy, you should be able to resolve the problem, 
assuming that the entire filesystem is not corrupt.

Reiser is based on Hans Reiser's doctoral thesis.  It works very well 
with lots of small files and if I recall correctly, it can allocate 
additional inodes as needed.  Reiser has been unstable and has been 
known to cause corruption.  I don't know if those issues have been 
addressed.

B trees can improve performance, but there are other issues as well.
The choice of a journaling filesystem is a system tuning issue.  Will 
you be storing a lot of large files or a lot of small files?  If so, JFS 
or Reiser might be the better choices.  In other words, match your 
filesystem needs to the capabilities of ext3, reiser, xfs or jfs.

If you want more detailed information, there are two books available on 
Linux filesystems:  Linux File Systems by Moshe Barr and Linux 
Filesysetms by William von Hagen.